Methods and devices for ventilating a footwell area of a vehicle, in particular of a motor vehicle, are known. In order to provide vehicle occupants with comfortable ventilation that ensures the air exchange in the vehicle and optimizes the thermal comfort, usually in combination with a heating and/or cooling of the vehicle interior, the interior areas around the seats are in particular given primary consideration. This also includes the footwell area or the footwell areas of the seats. In order to control the ventilation, flaps are usually used in ventilation and air-conditioning systems of motor vehicles, which flaps enable a variable air distribution, for example in the areas of window ventilation, individual fanning, and the footwell area.
EP 1 526 015 A1 by way of example discloses a flap of this type, which can be used in an air-conditioning unit or the central air distribution unit of a ventilation system. The flap makes it possible to adjust the proportion of air that is fed to the footwell area of the vehicle, there being no distinction made here with regard to individual seats within the vehicle, the footwell area air having to be distributed, however, between individual seats downstream, after the flap. Merely a distribution between the front and rear footwell area can already be provided by the design of the flap and cooperation thereof with two corresponding air channels.
The vehicle occupants can typically preselect, via an operating device of the vehicle air-conditioning system, whether the air is to be distributed for window ventilation, for individual fanning, or into the footwell area, wherein it is very often also possible to select mixed settings. In order to heat a cold vehicle interior in winter operation, it is expedient here to select a setting of footwell area ventilation, in order to achieve on the one hand effective warming throughout the interior, wherein a natural convection on account of the lower density of hot air also causes this hot air to be transported into the upper regions of the interior, and in order to attain on the other hand a subjective feeling of warmth at the feet of the occupants. In order to cool a hot vehicle interior in summer operation, it is, by contrast, expedient to select the individual fanning setting in order to achieve an effective and turbulent cooling and mixing of the air in the vehicle interior (also assisted here by natural convection on account of the higher density of the cooled air) and in order to attain a subjective cooling effect in the region of the upper body and the head. Under conditions of climate transition, i.e. in moderately cool or moderately warm climate, it is expedient to select a mixed setting between individual fanning and footwell area ventilation. For this reason, an automatic air-conditioning controller usually also provides corresponding flap settings depending on the climate conditions.
In particular when setting the ventilation in summer operation, however, the extent to which a ventilation (in particular a proportionally small ventilation) of the footwell area in conjunction with the ventilation setting of individual fanning is advantageous is the topic of dispute. Among different population groups, in different regions of the world, but also among different individuals, there are quite different preferences in this respect. Many people perceive a cool flow of air in the footwell area, in particular when provided over a relatively long period of time, as an unpleasant draught. Here, lightweight leg coverings and/or open footwear can also particularly intensify such sensitivity. The usual local vicinity of the footwell area outlets relative to the feet and legs of the vehicle occupants (depending on which seat position a person occupies) can additionally cause an airflow of this type to be particularly noticeable, since it is conducted to parts of the body surface in a concentrated and directed manner. For other people, however, the subjectively perceived cooling effect is assisted in a rather pleasant manner when a little cool air is conducted into the footwell area, for example in an initial cooling phase following vehicle start-up with a heated vehicle interior.
In this context, a ventilation system is described, for example in WO 2014/036208 A1, in which a forced ventilation of the footwell area is provided by means of a bypass channel. This bypass channel makes it possible to provide a small amount of air for footwell area ventilation when this ventilation setting is actually switched off by the corresponding flap in cooling operation with the ventilation setting of individual fanning being selected. With the disclosed embodiment, an assignment of the bypass channel to the footwell area ventilation for the front region of the vehicle interior is evident. It is thus disadvantageous that there is no option to set a footwell area forced ventilation selectively and individually for any seat. It is also disadvantageous that the forced ventilation set by the bypass channel can no longer be influenced subsequently, depending on whether this may or may not be desired by a particular vehicle occupant.
A device by means of which a forced ventilation of the footwell area can be controlled depending on an external temperature is disclosed in KR20080010545. Both a degree of opening and a time of the footwell area ventilation are considered here in dependence of the external temperature. A certain differentiation is thus possible in respect of different conditions that can accompany the external temperature. A differentiation in respect of different people in the vehicle, however, consequently an individual setting of the forced ventilation of the footwell areas of all seats, is not disclosed here, either.